The present invention relates to a shelf stable food product, particularly but not exclusively a low fat food product, having a continuous aqueous phase with oil droplets and protein coated gas bubbles dispersed therein and a method for making the same and in.
Particularly in the West, obesity is a major cause for concern. Health conscious consumers are increasingly looking for products that have low fat and calorific content. However, they are often not prepared to accept healthier alternatives that have poor (or even different) taste and/or texture to the traditional products. Thus, food manufacturers face the problem of making low fat alternatives to some of the consumers' favourite products such as desserts, cooking sauces and salad dressings that not only taste as good but that also give the same texture and sensation in the mouth when eaten. Fat plays and important role in giving products their distinctive texture as well as taste. Although fat can be removed and/or substituted to produce a healthier product, if it does not have the same organoleptic properties as the equivalent “full fat” alternative it may not meet with customer acceptance. Moreover, many consumers are not prepared to pay a premium for a low fat alternative, it therefore being important that any new products can be manufactured in a cost effective manner.
Many fat containing food products such as sandwich spreads, soft cheeses, sauces and mayonnaises are emulsions of fat in water (having either a continuous water phase i.e. oil-in-water emulsions or a continuous fat phase i.e. water-in-oil emulsions).
It is known from EP1938697 that a class of proteins found in fungi called hydrophobins can be used to stabilise foams in aerated food products. Once hydrophobins are located at the interface they spontaneously aggregate to create a two-dimensional network. This network then allows air cells to behave as if they are oil droplets, thus producing what might be called an air filled emulsion, however, the application of hydrophobins in food products has been limited by their high cost. In addition, the hydrophobins spontaneously form into aggregate once at the interface which means that the production of the air pockets is uncontrollable. During the production process the hydrophobin aggregates can be knocked from the interface and become inactive, allowing the air pockets to break up thereby altering the formulation of the final product.
The use of air cells in food products is also described in WO 00/038547 where the air cells are used in the water phase of oil with water emulsions to equalise the density of the water and oil phases to prevent separation of the water phase. The air cells also reduce the tendency of the oil with water emulsions to spatter when used in shallow frying by providing nucleation sites for evaporation of the water phase.